Probably because old calendars (such as the Persian Calendar) used 360 days for a year-when they watched the stars they saw them revolve around the North Star one degree per day.
September 27, 2015 will bring a supermoon lunar eclipse at nightfall. The last lunar eclipse of this magnitude occurred in 1982, and the next one of a similar magnitude will be in 2033. A lesser lunar eclipse will come in 2018. The lunar eclipse part of this phenomenon, according CTV, is caused by the Earth inserting itself between the sun and the moon. As this happens, the Earth casts its shadow on the face of the moon.
The next one is due Oct. 8, followed by blood moons April 4, 2015, and Sept. 28, 2015, according to NASA. There will be a total lunar eclipse on those dates, when the moon passes into the Earth's shadow, and the moon will begin to appear bright orange or red because of the way sunlight bends through the Earth's atmosphere.